Primary Bone Vascular Neoplasms: An Integrated Biological Perspective from Bone Pathology to Precision Oncology.

Primary bone vascular neoplasms comprise a rare and biologically heterogeneous group of endothelial tumors encompassing benign, intermediate, and malignant entities with distinct clinicopathological, molecular, and prognostic characteristics. These tumors remain diagnostically and biologically challenging because of overlapping histopathological features, heterogeneous clinical behavior, evolving molecular landscapes, and limited disease-specific evidence. Advances in bone pathology, immunophenotyping, molecular diagnostics, and genomic profiling have substantially improved tumor classification and biological characterization. Importantly, contemporary classification and molecular studies have also highlighted the biological heterogeneity of vascular lesions involving bone, distinguishing well-defined vascular neoplasms from vascular malformations and identifying additional molecularly defined entities relevant to osseous disease and differential diagnosis. Concurrently, increasing recognition of the bone microenvironment and osteoimmunology provides a broader framework for understanding interactions among endothelial, skeletal, stromal, and immune populations and the extracellular matrix, with potential relevance to angiogenesis, bone remodeling, and tumor biology. Previous authoritative syntheses have established the classification, molecular features, diagnosis, and clinical management of these neoplasms. However, comparatively limited attention has been devoted to integrating tumor-intrinsic alterations with vascular-bone crosstalk, extracellular-matrix and mechanobiological signaling, osteoimmune regulation, and emerging precision-oncology strategies. Building on these foundations, this review integrates current evidence on classification, molecular pathogenesis, the skeletal microenvironment, osteoimmunology, biomarkers, and precision oncology. Where relevant, molecularly defined vascular neoplasms and vascular anomalies involving bone are discussed to clarify classification, molecular context, and differential diagnosis without conflating these lesions with the principal WHO-defined primary vascular neoplasms of bone. Findings directly demonstrated in primary bone vascular neoplasms are distinguished from mechanistic concepts extrapolated from physiological bone biology, other bone tumors, or non-osseous vascular neoplasms. Through this evidence-calibrated approach, we propose an integrated vascular-bone-immune framework, identify key knowledge gaps, and define priorities for disease-specific translational research and more individualized patient management.